The CDC sounding an alarm second case of the mysterious and sometimes deadly virus known as murderers here on US soil. This time in Florida the first victim was diagnosed ten days ago in the midwest but both patients had been in Saudi Arabia. So can people here in the US catch the virus. Here's ABC's Steve doesn't -- This new and deadly disease is traveling into the US with unsuspecting passengers on airlines. Today the CDC is announcing that a second patient in the US has been diagnosed with Merck's or Middle Eastern respiratory syndrome. This time in Orlando a medical professional from Saudi Arabia. Who was here visiting family and had to be hospitalized an isolated -- corona virus has no vaccine and there's no treatment that we know that works the world's top doctors believe the disease came from Campbell's in the Middle East and spread largely to health professionals there will be treating the sick. The symptoms resemble the flu fever cough and trouble breathing. More than 530 people have gotten sick. A 145. Have died. Tonight the CDC is trying to calm fears saying the disease spreads -- repeated and last in contact with an infected person. Medical professionals most at risk. But they're still trying to track down the passengers who may have been exposed on the Orlando patients flights on May first. He flew from jet out to London London to Boston. Boston to Atlanta and Atlanta to Orlando 500 travelers on his US flights alone. Investigators here the CDC are hoping to task each one of those potentially expose passengers. The first US case appeared in Indiana last month another medical professional who worked in the Middle East both patients on the mend tonight. Steve -- Centanni ABC news Atlanta.

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